Electric connecter



BEST AvAxLABLE cop".

Oct. 26 1926.

R. V. BVINGAY ELECTRIC CONNECTER Filed oct. 2'?, 1919 wwww Patented Oct. 26, 1926.

UNITED" STATES,

sesrAv/ MLABLE ooe- Parr1511151111 OFFICE.

ROBERT v. BINGAY, or PITTSBURGH, EN'NSYLVANIA. AssIGNoB. 'To PITTSBURGH TRANSFORMER ooIvIPANY,v A CORPORATION or. PENNSYLVANIA.

ELECTRIC CONNECTER.

Application ned october' 27, 1919. Y semi No.. 333,738.

This invention relates to bus bar or heavy current leads and particularly to such leads as those of transformers, Where the current is passed through the transformer casing, the inner lower ends of such leads being connected to wires from the coils and the upper outer ends to the supply or distribution circuits. The object of the invention is to provide such leads or terminals which will be simple and rugged in'construction. well insulated from the casing and aifording a large contact area for attachment of the conneoting conductors, and will be dust and water proof and air-tight.

In priorlleads the conductors have been insulated from the ground by means of an in sulating bushing having a central aperture of 'considerably larger diameter than the conductor which is to pass throughit.Y The space between the conductor and the inner wall of' the insulator is usually filled with a cement tohold the conductor in position. It Ahas proven ditlicult to obtain a uniform 'filling of this space, and bubbles are created, and confined air spaces, causing marked concentration of electrical stress at certain points and heatinguip ofthe insulator with resultant breakdowns. It has therefore been necessary'to'employ insulating bushings of considerably larger size than the voltage requirement and at correspondingly greater cost. Further objections to prior leads are the diiiiculty' and expense of-providing them with end contact castings which mustbe separately machined and threaded'onto each end of the 'lead for attachment to'thej connecting condiurtors."l

The structure of this invention makes it possible to provide each lead as an 'integral strip'having-the 'desired contact ends Without extra' parts or machining no cementing or fitting of the lead in its bushing is required and the parts are so formed that-'all portions of the insulation are subjected 'Ato equal electrical tension without dangerous areas of stress concentration. I

Other'objects and advantages of the invention will appear in the following description of specific embodin'ients taken with the accompanyin;r drawings in which Fig. lis a plan view ot' a transformer lead 'andvbushing illustrating one embodi ment of the invention, and

Figs, 9 and 3 are vertical sections thi-@ugh the same illustrating the parts in place on the transformer.

In the embodiment of the invention illustrated in Figs. 1 to 3 a pair of flat drawn copper hars 5 are provided with' a short intermediate spacer strip 6also of drawn copper. The three bars are fastenedv together as shown and positioned centrally inthe bnshing support 7 While the insulator 8'in plastic state is pressed andlim'olded `into the shapeA shown and then hardened to-liold thebars in place in the b'ushngi-andprouide xthe necessary extensions above' and"below to avoid surface leakage'v-ifv "wir:

The bushing support?risfofbraiss'or'other non-magnetic -materia-1': toa 'avoid` f magnetic iux effects, heatingfandilnqual Ie'lectr-ical stresses likely to be set'up'fin-'Inagntic material by heavy alternatingfgcurrents; in the has a disk'bo'ldy` 95andeentrlutubiilariportion 10 with alroundedlupper,endllslhis central tubular portion not:only' affords' good mechanical tcnnection Withitliefinsu-l'ator but also en larges the zgronild area' manyfold'and f distributes the fcapacity stress, tlfuse'permitting the employment oa much thinner. insulati`on section and resiiltigiina safelf, more com pact and unitary .'dev'icef z'llheirbiishin'g support- -7 and L insulator 8'fre preferably l oval or ell iptical in Asection and -f thisehaping taken' with the'- perfectlyV homogeneous coinpositiono-fthe pressd2and-moldedfinsulation gives; substantially i even distribution rf stressesf The? insulatori -nfandms'u'pprting parts maytherefore ifbe .madegrelatively smaller without-"danger E"olli vrupt'ure and, with consequent' saving -in' sizes'fofE ail- :thezrelated partslf The molding-of the insulator in place also provides a Iiuggedly'strong construction in 'ivhich thepartsare alli dusti=proof and waterproof tandf-irmly and--di1rably secured together. andi any desired frr or ure of: the@ spacedv -iiat strips Apermits; A all surfaces to be simultaneously, brought vinto tight engagement With the connecting conduetors. -.The rspacing of .the leads by @QP- per strip 6 also .givesa .greater 'Conducting cross section Within 'the insulator reducing internal heating and permitting .the-leads.

themselves to be ot' thinner' stock.

In the embodimentfshourn ,fin Figs. Lito 3 each bushing support I of a series is provided Yulith afring 'flange '17 for positioning on a flange 1S ot the transformer :top 19y as shown :and rthel'bu'shingsupport7 .is fastened iin "plac'ely bolts Q0 between disk 9 and Vbosses on the top f-l'9.

'While fthe invention has been illustrated -ifn connect-ionfwth :specific embodiments it -is inot lconfined;.theretou'but :is intended to cexlersuch modifications thereof as afall with- -i'n-lthe 'sope .olf the appended claims.

met lel'eim is:

:1. :.nfinsulated lead structurecomprising #a bnshinglsupport formed-by a body portion and an oval tubular :portion fextending 'theretrom rthe7 body vperrtion :being adapted 'to'be Vdetae'liebly secured 'to ia transformer easing'and tlienubular :pertion extending `there- 4tlrrouglnaconductor comprising plurelity tiet-)bars sspacedapart by-a?r flat metal Lmember4 of: high conductiwity passing. centrailly through .seid -ltub'ulafr portion and ipiiralle'llto lt-he axis ot-saidsova'l, and imsnlattxr'mf homogeneous material molded in centactflfwithf'the Walls of Vseid tubular 'portieri and fwith seid :conductor so; aste-support A said lcenthlctorfdrom :said ybushing support.

.fsecinedi tothe exterier :of e. vcasing :and a l'imt'ular :portion adapted? .to aextend through 'thevces' fa eond-.uctonpessing .centrally .'-thiteu'gh e-itiiliular-portiouandi a homogeneous finsulatingfmaterialmolded and pressed tinto icentact with-fthe: malls of #said ztubular -portion 'and Withsaid conductor so as to support.v said conductor Vfrom said support, the said conductor havingincreased cross section Where surrounded by the supportv Vsotlrat the current density and'heating fare'reduced Where Athe conductor surfaces'a're not exposed.

4eV In an insulated lead structure the combination of a support comprising a nonmafgnetic gplateadluzpted to be detachably secured to the exterior of a. casing and u tubular .portion adapted -to extend through 'the casing, a conductor lpassing `centrally through ,the tubular portion, and a .hemo- -geneous --insulating `material molded `and pressed -inte Contact with the-.Walls ot'seid tubular -portion and -with 'said conductor ,so -usltosupport saidconducter 4from said .support, the :sa-id conductor hav-ing. increased fcross section Where surrounded .by the support so that the eurrentfrdensity and .heating :ere reducedwhere the `eenductor surfaces are fnolt exposed, 'the ,saidfyeonduetor comprising n plurality of Efiat; ,bars ,spaced .apart by a flat metal membenef high conductivity substantially :equal 'ini-length ,fte ,that ,part of the-:lead which is surrounded by insulating fmuteriad. A

f f5.l an insulated lead estructura: `the `,com- ,fbina-tion Toti a fbushng support Yet{1101111.15143} matic metzlfeomprisinga tubularydepending @portion elongated cross section .and a :body ,portion iba-ving, an outwardly extend- --mg'langef-edaipted to ,receive-clamping means,` e: seating ,portion,- a conductor comprising abar 'of Yelongated rect-angular, cross :section tormedwfromfa plurality ofilat vhars :spacedapart by flat ,metal-member ypasseen'tra-lly throlghgsaid'tubular portion, :and homogeneous insulating materia-l molded and rpressed into contact f with `said confduetor end :said tubularportion` so :as-,to :wsupp'ort the' conductor on the support.

A6'. yln an insulated-lead structure `theeorn- A`hinution o-a fbushingsupport of nonmaginetic material-:comprising a tubular depend 'mg portion fot 'oral cross ,section .and fa bodg7 portion having an outwardly .extending fange adapted to 'receive clamping means, a conductor-1 comprising a metallic barof elon- -ga'ted :rectangular cross section ,passing cen- -trally-through said tubular port-ion, and homogeneous' insulating .material lmolded "and- .pressed zintoeontaet with said conductor andxsarid-itubidar@portion sol as to support the-zconduc'tor-fon 'the support, fthe-,said eenductor having inereased cross section Where :surrounded-hy theg'bushing support .so that lthefeurrent-:density and Iheating @are reduced #there 'the conductor sur-faces are not exposed.

' RoBfERT -V...BINGAY. 

